JPS6241788A - Far infrared ray heater and manufacture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a far-infrared heater and a method for manufacturing the same.

(Prior art) Conventionally, in order to produce a product using a molded body of a ceramic material such as aluminum oxide or glass whose main component is silica, and forming a conductive film or a heat-generating resistor film on its surface, Metals and metal oxides can be deposited using vacuum evaporation, sputtering, ion blasting, plasma spraying,
Air plating methods, conductive paint coating methods, etc. are used.

Further, a far-infrared heater that mechanically combines a heating wire and a radiation plate is also known.

(Problems to be Solved by the Invention) The conventional manufacturing methods and devices described above require troublesome manufacturing operations and high manufacturing costs, and are not necessarily effective as far-infrared heaters.

(Means for solving the problems) The present invention solves the above problems and has a wavelength of 4 μm to 100 μm.
The present invention provides a stable and robust ceramic far-infrared heater capable of emitting far-infrared rays in the μm range, particularly 8 μm to 15 μm, which is effective for the human body.

That is, the far-infrared heater of the present invention has acetonate indium acetate In (OAc)x on the surface of the ceramic molded body.
(ac ac), -x (where Ac is an acetic acid group.

X integrally comprises a fired thin film made of an oxidative decomposition product of 0 to 3].

The present invention further provides a method for producing the above-mentioned conductive heater easily and economically, in which a solution of indium acetonate acetate or a small amount of tin alkoxyhalide is added to the surface of the heated ceramic molded body. Sn
A solution containing Oly (OR)4-y (where R is an alkyl group and y is 0 to 3) is uniformly deposited and a heated oxidative decomposition reaction is performed to form a fired film mainly composed of tin oxide. It is characterized by causing generation.

(Example) As the ceramic material, various conventionally known ceramic materials can be used, but preferably aluminum oxide Al2
A composite ceramic material containing zirconium oxide Z r O@ alone or as a main component is used. According to the present invention, such a ceramic material molded body, for example, a plate-shaped molded body, is heated in an electric furnace or the like, and the heated surface is coated with Here A
o is an acetate group, X is an acetonate indium acetate solution with the composition of
(Here, R is an alkyl group, and y is 0 to 3). The molten tungsten is applied uniformly to the entire surface by spraying or coating. The solvent is
Water, alcoholic solvents, ester solvents, aromatic solvents, and other organic solvents may be used alone or in combination. The heating temperature of the molded body is 300°C, which is sufficient to cause the solution to undergo a heating oxidative decomposition reaction and to form a fired film with conductivity of several 100 μm or more, mainly consisting of indium oxide or a composite oxide of indium oxide and tin oxide. or more preferably 450" (: or more. Thus, generally several 10 ohms/ro or more or more several 100 ohms
A speech resistor film having a resistance of Ω/Ω or less is obtained. The thickness of the fired film is generally from several microns to several hundred angstroms, and a stable and robust product that firmly adheres to the surface of the molded product can be obtained. A heating element film with reduced manufacturing costs can be obtained without requiring any additional work.
Moreover, the fired film is transparent and has a good appearance. In addition, when the solution is applied to the surface of the molded body by spraying, the amount of spraying can be easily adjusted, and a fired film can be obtained immediately and uniformly, and the conductivity can be easily adjusted, so that a predetermined variety of conductivities can be obtained. It is advantageous to be able to obtain a ceramic molded body with

Next, as a specific example of the present invention, 8 μm which is useful for the human body.
A far-infrared heater that can generate far-infrared rays having a wavelength of 15 μm in a particularly large amount will be explained.

In(OAc) x (aoac), -x (where Aa is an acetate group and X is 0 to 3) is dissolved in methanol in an amount of i, oOmol/l, and the acetonate is equivalent to 2 m01% of the indium acetate. , 02 mol/l of 5nOly(OR), -y (where R is an alkyl group, y is O~4) was added and dissolved in a solution that was preheated in an electric furnace to 105 mol/l.
A plate-shaped aluminum oxide molded body measuring 105 mm x 5 mrn (thickness) was heated to 500° C., and a spray gun was used to uniformly adhere to the entire surface of the heated surface at an air pressure of 1 kg/cn'. Spray pressure is 0.4 kl
? /c% - 2.0 kg/crd is generally the range, but around 1 kg/cra is preferable, and it was possible to spray with good mist particles.

The adhering mist particles immediately undergo an oxidative decomposition reaction due to the heated surface of the ceramic molded body at a high temperature of around 500°C, resulting in a thickness of 1 μm consisting mainly of a composite oxide containing a small amount of tin oxide mixed with indium agglomerate. Resistance value 200-30
(A conductive thin film was obtained in the range of 1/2 mm.Thus, the material that was left to cool to room temperature was a ceramic film having a good conductive heating resistor film that adhered strongly, stably, and firmly to the surface of the ceramic molded body. An infrared heater was obtained.In order to test its performance as a far-infrared heater, silver electrodes were baked on both edges of the plate and electricity was applied to it. When we measured the amount of far infrared rays generated by the film, as shown in Figure 1, the amount of far infrared rays emitted with a wavelength of 8 to 15 μm, which is particularly effective for the human body, was extremely large, but near infrared rays, which can cause burns, It was found that a characteristic in which the amount of generation is small can be obtained at a wavelength of .

Figure 2 shows a conductive ceramic produced in the same manner as above, except that zirconium oxide (ZrO) was used instead of Al (○) as the ceramic molded body, and the same far-infrared radiation test was conducted. Showing the measurement results,
Similar to the above, it was praised as a particularly advantageous product as a far-infrared heater.

We investigated the relationship between solution spray time and solution concentration when the air pressure was kept constant at 1 kg/crA, and found that the concentration of indium acetonate acetate was 510.65 mol/l to 5 m
In the OL/L range, the time varies from 2 to 10 seconds, but all you need to do is spray short poems. Spray pressure is o, 4k
y/cI+I ~2. Generally, the range is Okg/cf.

Next, we investigated the relationship between the conductivity (resistance) of indium acetonate acetate alone and a colored solution in which tin alphoxychloride was added, and the results shown in Figure 3 were obtained. As shown in FIG. 3, the resistance value changes depending on the amount of dopant added. Generally, the amount of Sn added is 10
Mo is preferably up to 1%.

Thus, heating resistor films having different resistance values can be obtained depending on the application by controlling the amount of dopant added as described above.

When the heating temperature of the molded body is 300°C or higher as shown in Figure 4, conductivity can be obtained, and in the case of an infrared heater, it is desirable to have several hundred 0/mouth, so in order to obtain this, it is preferably about 450°C or higher. .

The amount of solution sprayed was as shown in Figure 5 when the solution in the above specific example was used.

In this way, heating resistor films with various characteristics can be obtained by adjusting the heating temperature and spraying amount.

Although the composition of the fired film of the present invention is currently unknown, judging from the fact that it is not a pure oxide, the reason why it can become a heat generating resistor is that metal atomic ions such as metallic indium and chlorine ions due to crystal structure defects. It is assumed that this is because it flourishes as an electron donor and acceptor.

In this way, when the ceramic molded body is heated, an acetonate indium acetate solution or a solution containing tin alphoxybanide is attached to the heated surface, and the degree of oxidative decomposition is forgotten by heating. Therefore, it is possible to obtain a conductive ceramic based on indium oxide alone or a composite oxide of indium oxide and tin oxide, which is firmly adhered to the surface of the ceramic molded body, and its production cost is low and it can be manufactured over long distances. It has the effect of providing an excellent material as an infrared heater.

[Brief explanation of drawings]

Fig. 1 is a graph showing the far-infrared radiation characteristics of the product of the present invention, Fig. 2 is a graph on the other side, and Figs.
2 is a graph showing the relationship between the blending amount of /Sn, the heating temperature of the molded body, the spraying amount of the solution, and the conductivity of the obtained product. 2 people outside Figure 1 Figure 3 Figure 4 Winding plate: JL degree (0c) Srn (rr + Ofl'10) Figure 2 Figure 5 IIfm outside m2

Claims (1)

[Claims] 1. Indium acetonate acetate (In(OAc)_x(acac)_3_-_x) (
Here, Ac is an acetic acid group, and x is a far-infrared heater that integrally has a fired thin film made of an oxidative decomposition product of 0 to 3). 2. A solution of indium acetonate acetate or a small amount of alkoxy tin halide (SnCl_y(OR)_4_-_y) (where R is an alkyl group and y is 0 to 3) is mixed on the heated surface of the ceramic molded body. A method for producing a far-infrared heater, characterized by uniformly depositing a solution and carrying out a heating oxidative decomposition reaction to integrally produce a fired film mainly composed of tin oxide. 3. Manufacturing the far-infrared heater according to claim 2, wherein the heating temperature of the molded body is 300°C or higher, and the solution is uniformly adhered to the surface heated to the temperature by spraying. Law.